Process for making metal matrices.



No. 888,881. Y PATENTED AUG. 25, 1808.

` E. ALBERT. PRUGESS POR MAKING METAL MATRIGES.

APPLICATION FILED OUT. 4, 1906.

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EUGEN ALBERT, or MUNIeH, GERMANY.

PROCESS non MAKING METAL Marmaris.

I Specification of Letters Patent.

Application lred; October 4, 1906. Serial No. 337,421.

Pacentedvaug. 25, 1968.

To all whom 'it may concern? .R

Be it known that I, EUGEN ALBERT, a subject of the Emperor of Germany, residing at 55 Schwabiiigerlandstrasse, in Munich, in

the Empire of Germany, have invented certain new and useful. lm rovements in Processes for Making Meta Matrices, yof which the following is a specification.

This invention relates to a process for the production of matrices for the reproduction y electro deposition of printing blocksv or forms, wood blocks, autotypes, and the like, and has for its.` object to render the process more effective and to avoid the heavy pressures which have been necessary hitherto. In molding metal matrices of 'half tone blocks, woodcuts, types, and the like,rit has been necessary to use an interlayer of such a consistency that it will allow of the metal matrix being pressed thoroughly into the deepest cavities of the original in order that such cavities shall be properly reproduced in the new block, this being necessary for printing therefrom. Such a method isset forth in my British Patent No. 81.17 of 1904. By using suchy an interla ing substance, softer than the matrix meta the material of whichis prevented from spreading sidewise, the use of,

great pressures is avoided and good results may beobtained. If the matrix be of lead sheet, a suitable interlayer could be formed of lead balls, or shot with means for preventing them moving sidewisegvwheir pressure is applied the .small balls would be compressed by the press platen to an even surface on those parts which are'opposite the high parts of the original, but opposite the cavities of the original wherethere 1s no resistance the lead sheet of the matrix would be bent doWlljWit-houtaltering the form of the balls. This result may be obtainedV by various means such as grooves, corrugations, or the like'and ,they

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are referred to generally in this specification as projections since they may be also in the form of squares or grains. A convenient projection for this purpose isl madewith alternate ridges and grooves on the adjoining faces of a aten and the back ofthe matrix res ective y.

he process is illustrated diagrammatically in the accompanying drawing, -in which:-

Figure 1 is a sectional View showing a platen with hard grooves and a grooved matrix ofI softl material before pressure' is applied; Fig` 2, 1s a sectional viewshowing the alteration in the-disposition ofthe material of the maadjacent surfaces trix after pressure is applied; and Fig. 3, shows a modification in which the hard grooved surface is formed on a separate interlaying plate.

Similar letters refer to similar parts in the` several views.

In the drawings P represents the platen of a press, Q re resents the material of the inatrix, and Pl) represents the original block which is to be re reduced; the recesses u,

and m, represent arge cavities iii the block much exaggerated to explain the working of theI invention `while k, lr, indicate small cavities.

It will be evident that if the ridges are too wide apart corresponding ridges would show themselves in the front surface of the matrix when subjected to pressure and in practice they shou d not be more than about l-lth of an inch deep therefore.'

5 The invention consists in a process of pressing with a hard surface such as P having projections thereon an adjacent back surface of the matrix block Q having projections in the soft material thereof. It will be seen on reference to the drawings that the small cavities such as lc on the high part o, o of a printing block are filled before the large cavities such as u and m and that the further pressure required to press the matrix into u and m with ordinary flat 'surfaces between the' platen face and the matrix back would cause shearing of the material in the cavities c to the detriment of the matrix face, owing to the fact thatthe matrix material on the high parts under such circumstances must move sidewiseto allow of the further descent of the A platen; by forming projections between the of P and Qthe margin of pressure required to fill the deep cavities u and m is amply provided for without any lateral movement vof the material opposite the hi' h arts of the matrix taking place, since t e ard surface P of the platen resists deformation and becoming embedded in the soft material of the matrix prevents its lateral movement, and also the ollows between the projections provide space for the recep-` tion of the surplus matrix material.

Figs. 1 and 2 show a grooved platen and a grooved lead matrix before and duringv pressure, Fig. 2 showing plainly the additional effect of the double grooving a the wide cavity u while oppositelthe high jwarts 0, o of the ori inal block the grooves of the press platen ave entirely destroyed the original form of the lead grooves and being fully embedded in the matrixmaterial successfully prevent it from sliding aside.

As the size of the projections is limited for the reasons mentioned it would not always be practicable to lay the grooves of the hard and the soft material parallel and op osite to cach other and I preferably there ore form the grooves so that when brought together they may be at an angle to each other which i separate interlaying plate S; in this case the operation is as followsz-A slab of impressionable material Q having on its back surfaces a series of projections and recesses is subjected to pressure beneath a platen Pf' with a smooth surface 5 this preliminary pressure would of course not be sullcient to produce any lateral displacement of the substance of the matrix. Following this preliminary pressure a llate of hard material S having a smooth sur ace on one side and projections and recesses on the other is interposed between the platen P and the partially formed matrix Q, the smooth surfaces being placed together and the surface of the interlayer with hardprojections against the partially pressed back surface of the matrix with soft irojections; a final' pressure is now exerted by the )laten on the interlayer and the soft slab, an the matrix completed, the hard projections of the interposed plate revent ing thelateral movement of the partie esof the matrix. Preferably the projections on the interposed plate S will be at an angleof about T150 to the projections on the slab Q', as beore.

It must be understood that this process is applicable to other .ocsasions. i1pon which it is desired tomakematrices ofsoft-metal and is notlimitedto the reproduction of printing blocks. onl

lai1n as my invention and desire L.Letters Patent is L .1 oeessof producing a matrix consisting in forminga lslab of impressionable 'materialjn the. back surface thereof. with a series of projections and recesses, laying the said slab with its back surface againsta hard surface having a series of rigid projections and recesses thereon and its front surface against the surface of the original block tobe co ied, and subjecting the impressionable slalla to pressure between the block and the said hard surface, substantially as herein de-v scribed. j

2. The process of producing a matrix consisting in forming a slab of impressionable material on the back surface thereof with a series of alternate ridges and grooves, laying the said surface with its front surface against the surface of the original block to,be copied and its back surface against a hard surface composed of a ri id series of alternate ridges and grooves so t at the grooves of the rigid surface are parallel and directly opposite to the grooves on the irnpressionable slab, and subjecting the im ressionable slab to pressure between the bloc and the said hard surface, substantially as herein described.

3. The process of producing a matrix consisting in forming a slab of impressionable material on the back surface thereof with a series of alternate ridges and rooves, laying the said slab with its frontsur ace against the surface of the original block to be copied and its back surface against a hard surface composed of a rigid series of alternate ridges and grooves so that the grooves of the 'rigid sursisting in forming a slab of impressionable material on the back surface thereof with a series of projections and recesses, subjecting the said slab to a preliminary pressure with its backvsurface against aflat surface on the pressing mechanism and its front surface against the surface of the blockan`d then subjecting the half formed matrix to a final pressure with its front surface against the surface of the block to be copied and its back surface against a hard surface having a series of rigid rejections and recesses thereon, substantial y as described.

lntestimony whereof I have affixed my signature in presence of two witnesses.

.i EUGEN ALBERT. Witnesses:

i AH. D. JAMEsoN, F. L. RANDs. 

